Remember when rock was young?

One old crock, two old crocks, three old crocks rock. Jim White winces to the music

They have been out in force this week: decrepit, creaking, past- it, a once-intriguing concept now in serious need of a walking frame. Yes, those gags and sneers about old rock and rollers have had a field week. Fats Domino, Chuck Berry and Little Richard came to Britain for a tour - the antiques road show the Guardian called it - accompanied by hoots of derision. On Radio 4's Today, Little Richard - proof of the age-defying benefits of snorting cocaine from the breasts of call-girls - popped up to suggest that rocking and a-rolling was a perfectly legitimate career for a 62 year old; he had absolutely no intention of retiring, he added. John Humphrys, a stripling of 52, could barely suppress his sniggers.

Then, on Thursday, Domino, the greatest of all rock and roly-pollers, collapsed after a performance in Sheffield. Diagnosing post-pneumonial infection of the trachea, doctors ordered the 67 year old to rest. His was a medical condition that unleashed not sympathy but unlimited chortling about how rocking past a certain age can severely damage the health. Laugh? I thought my plectrum would burst.

As the retire-by date for rock practitioners has been pushed back over the years - largely by those who in earlier times suggested theirs was no business for oldies - we have been confused as to how we should respond. Laugh, or buy the records? The ever-ageing profile of rock has reached the point where all five of the top five biggest-selling recording artists in Britain last year (Phil Collins, the Stones, Elton John, Eric Clapton and Sting) are of an age previously considered inappropriate for such a calling. Particularly if, in the case of Elton John, the calling includes the necessity of wearing flesh-coloured plastic Versace suits to work.

And this is the point about old rockers: it is not the age that makes them ludicrous, but the contents and presentation.Thus Johnny Cash, aged 63, appearing at the Albert Hall last week in his usual outfit of blackest black (none more black) looked about as cool as it is possible to look. The next day, however, he cancelled his tour and returned home to America suffering from such acute neural discomfort that he checked into a pain- management clinic. No gags about Johnny, though. Because his music is suitably dignified for a man of his age: popular maybe, but mature, considered, profound.

Alvin Stardust, on the other hand, although 10 years younger than Cash, never stops making us howl. He could be seen on Channel 4's Glam Rock Night recently saying that he did not understand why the press used the euphemism "ageing rocker" to describe him. "I'm old," he said. "Why don't they just say old?" A fair point, except the syntactical problem here is not with the term old but the term "rocker." Alvin, with his daft hair and bad songs, was a joke when he was 25. Being 53 is not his problem. It is being Alvin Stardust.

This rule - the Stardust rule - extends throughout the ever-ageing firmament of rock. Keith Richards, smirking above his chopping chords, loping around the stage with an ironic leer, looks more chic, more detached, more rock and roll with every advancing decade. He was always a near-death experience and, now that it is likely to happen at any moment, he couldn't be more compelling. Meanwhile Mick Jagger, obliged by his role in the band to strut about the stage in a parody of tight-bottomed youthful energy, looks ever more ludicrous.

Chuck Berry, on the other hand, the most cantankerous sod in a world of prima donnas, really works best as an old man, complainingly, churlishly, pumping out the rock and roll without the remotest hint of enjoying it. And he looks great, keeping trim on child brides. Rod Stewart, however, trying, at 50, to be sleek, sexy and youthful and equally youthfully attached, is just a prat.

Even the most cheerful old timer, though, can suffer when they are confronted by a frightening reminder of their past. Poor Dion DiMucci, performing here about four years ago, gave a stunning set of clever songs about urban decay, before, in his encore he was forced into a corner and made, by public demand, to strum out his greatest hit. Never has a 52 year old looked as embarrassed as this one was singing "Why Must I Be A Teenager In Love". He has not been back. And Pete Townshend, too, became so sick of "My Generation" he gave up on The Who altogether, suggesting that his brother take over his position in the band instead. "He looks like me, and he plays like me," he said at the time. And importantly, because he didn't write it, he could stand on stage and not blanch when the line "I hope I die before I get old" was sung.

But Fats Domino has no such youthful skeletons. He is due to re-appear, after his convalesence, on 30 June in Glasgow. It promises to be a fine night out, with nothing at all to laugh at, for anyone who likes the classics. Young or old.